In her trip through China's Suining County in Jiangsu province, journalist Mara Hvistendahl saw plenty of familiar signs of economic growth. But she also saw something at an elementary school that startled her: There were far more boys in the classrooms than girls.

After months of research, she discovered a wide gap in the ratio between boys and girls, not just in China, but in other parts of East and South Asia. In her book, Unnatural Selection: Choosing Boys Over Girls and the Consequences of a World Full of Men, Hvistendahl writes that wider access to ultrasound technology and abortion has allowed parents in these developing countries to abort daughters in the womb and keep sons.

The rise of an educated and wealthy clientele in many Asian countries has made sex-selective abortion more common. But, Hvistendahl says, there are a few key differences between the cultural context of abortion in Asia and the West.

"In the U.S., a woman may have to brave picket lines to get an abortion," Hvistendahl says. "She may not have a clinic in her town, and in many parts of Asia abortion is readily available, and so is ultrasound."

Hvistendahl adds that gender discrimination in developing nations does not fully explain the drop in the number of girls born. "You have countries where women have very low status — in the Middle East for example — and the sex ratio at birth is balanced," she says.

Gender imbalance comes, in part, from dramatic drops in birth rates. "The average Korean woman in the 1950s had six children. Now the birth rate is close to one," says Hvistendahl. "It's not that women necessarily want sons any more than before, but there's more pressure on them."

Hvistendahl explains that part of the drop in birth rates in Asia can be attributed to "a history of population control, and a dark history at that."

The Dangers Of Gender Imbalance

As an example of the consequences of sex selection, Hvistendahl says that in Taiwan, many men have difficulty finding wives using traditional methods. Some even spend thousands of dollars on "marriage tours" to other Asian countries.

The fee includes travel, lodging, and the purchase of women there. Hvistendahl says the problem is not limited to Taiwan, but also South Korea, and is growing in China, India, Albania, and Azerbaijan as well.

As men find it more difficult to find wives in these countries, Hvistendahl says, "it is leading to unrest and almost certainly will lead to more." Unmarried men are responsible for more violent crime than married men. And Hvistendahl adds, research in eastern China showed a correlation between a high male-to-female sex ratio and the crime rate.

'Consumer Eugenics'

Although sex-selective abortion has not been as popular in the West as in Asia, Hvistendahl points out that some families in the West use in vitro fertilization, which allows them to choose the gender of their children. Hvistendahl says in the West, parents that use this method choose to have girls more often than boys.

"I actually think Americans selecting for girls is really not that different from what's happening in Asia," Hvistendahl says. "In both cases, parents are going in with preconceived notions about how the child's going to turn out, and it's really, in both places, this shift toward consumer eugenics and toward parents making small decisions over how their child's going to turn out. And, you add those decisions up and they have a big impact on society."

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